'externalptr' error in R using XML data

Question

I am working with some XML data in R and running into errors regarding type \'externalptr\'.

1) I get the following error when I try to use the xmlInternalTreeParse()

Answer 1

I know this is an old thread, but to understand in detail about external pointer I feel it is important to understand when it is used. This thread tells the difference between xmlParse and xmlTreeParse, when to use it, and how it works (pointer vs object).